At present, the technique of attaching or printing a barcode to an article (or a product), and inputting the information on the article into a cash register or a computer used for managing articles, by reading the barcode with a reading apparatus having a scanner has been widely spread (see patent document 1). A barcode used for such a technique typically represents numbers or characters by varying the widths of lines arranged in a striped pattern. Also, a barcode is a one-dimensional code that has information only in a lateral direction.
In recent years, a two-dimensional code, such as a QR code (trademark), that represents numbers or characters by arranging dots in longitudinal and lateral directions has been also spread. A two-dimensional code can hold a large amount of information in itself by encoding the information, compared to a one-dimensional code such as a barcode, and therefore, a two-dimensional code is used in fields where a large number of information is handled, such as part ordering management in huge factories, product shipping management by wholesale dealers, or product sales management in vending machines (see patent document 2). Also, the technique of providing a mobile phone having a built-in camera and the function of reading a two-dimensional code; reading a two-dimensional code printed in a leaflet by using the mobile phone having a built-in camera; and thus conveying information on products, services, events or the like through the two-dimensional code and the mobile phone having a built-in camera recently has been spread.